﻿using System;
using UnityEngine;

public enum GridShapeType
{
    /// <summary>
    /// 正方形
    /// </summary>
    Square,
    /// <summary>
    /// 正六边形
    /// </summary>
    RegularHexagon,
}

public class MapGridCtr : MonoBehaviour
{

    private const float MAXDIS = 10000001f;
    /// <summary>
    /// 网格线是否显示
    /// </summary>
    public bool showGrid = true;

    /// <summary>
    /// 网格线宽度
    /// </summary>
    public float gridLine = 0.1f;

    /// <summary>
    /// 网格线颜色
    /// </summary>
    public Color gridColor = Color.red;

    /// <summary>
    /// 网格线
    /// </summary>
    private GameObject[,] m_lines;

    /// <summary>
    /// 一个网格的基数
    /// </summary>
    public int coefficient = 8;

    /// <summary>
    /// 当前地图地形
    /// </summary>
    public Terrain m_terrian;

    /// <summary>
    /// 当前地图地形行数
    /// </summary>
    private int m_arrRow = 0;

    /// <summary>
    /// 当前地图地形宽度
    /// </summary>
    private int m_arrCol = 0;

    /// <summary>
    /// 当前地图vector3数据
    /// </summary>
    public Vector3[,] m_array;

    /// <summary>
    /// 网片形状
    /// </summary>
    public GridShapeType m_meshType;

    public SelectObjects select;
    protected void Start()
    {
        this.LoadMap();
        select.Init(transform);

    }

    /// <summary>
    /// 加载地图数据
    /// </summary>
    public void LoadMap()
    {
        if (this.m_terrian == null)
        {
            Debug.Log("地形为空!");
            return;
        }
        if (this.m_meshType == GridShapeType.Square && this.coefficient < 2)
        {
            Debug.Log("网格基数必须大于2!");
            return;
        }

        TerrainData data = m_terrian.terrainData;
        int mapz = (int)(data.size.x / data.heightmapScale.x);
        int mapx = (int)(data.size.z / data.heightmapScale.z);

        this.m_arrRow = Math.Min(data.heightmapWidth, mapz);
        this.m_arrCol = Math.Min(data.heightmapHeight, mapx);

        float[,] heightPosArray = data.GetHeights(0, 0, this.m_arrRow, this.m_arrCol);

        this.m_array = new Vector3[this.m_arrRow, this.m_arrCol];

        for (int i = 0; i < this.m_arrRow; ++i)
        {
            for (int j = 0; j < this.m_arrCol; ++j)
            {
                //this.m_array[i, j] = new Vector3(j * data.heightmapScale.x-1000, heightPosArray[i, j] * data.heightmapScale.y, i * data.heightmapScale.z-1000);
                this.m_array[i, j] = new Vector3(j * data.heightmapScale.x, heightPosArray[i, j] * data.heightmapScale.y+2, i * data.heightmapScale.z);
            }
        }

        if (this.showGrid)
        {
            this.ShowGrid();
        }

    }

    /// <summary>
    /// 显示地图网格
    /// </summary>
    private void ShowGrid()
    {
        switch (m_meshType)
        {
            case GridShapeType.Square:
                {
                    this.ShowSquareGird();
                    break;
                }
            case GridShapeType.RegularHexagon:
                {
                    this.ShowRegularHexagon();
                    break;
                }
            default:
                {
                    Debug.LogError("暂不支持此形状！ m_meshType： " + m_meshType);
                    break;
                }
        }

    }

    /// <summary>
    /// 显示正方形网格
    /// coefficient代表边的网格数，最小为2
    /// </summary>
    private void ShowSquareGird()
    {
        Vector3[] pos;
        int rn = this.m_arrRow / (this.coefficient - 1);
        int cn = this.m_arrCol / (this.coefficient - 1);
        if (this.m_arrRow % (this.coefficient - 1) > 0)
            ++rn;
        if (this.m_arrCol % (this.coefficient - 1) > 0)
            ++cn;
        this.m_lines = new GameObject[rn, cn];

        for (int i = 0; i < this.m_arrRow - 1;)
        {
            int lastr = i + this.coefficient - 1;
            if (lastr >= this.m_arrRow)
            {
                lastr = this.m_arrRow - 1;
            }

            for (int j = 0; j < this.m_arrCol - 1;)
            {
                int lastc = j + this.coefficient - 1;
                if (lastc >= this.m_arrCol)
                {
                    lastc = this.m_arrCol - 1;
                }

                if (lastr < this.m_arrRow - 1 && lastc < this.m_arrCol - 1)
                {
                    pos = new Vector3[this.coefficient * 4];
                    for (int k = 0; k < this.coefficient; ++k)
                    {
                        pos[0 * this.coefficient + k] = this.m_array[i, j + k];
                        pos[1 * this.coefficient + k] = this.m_array[i + k, lastc];
                        pos[2 * this.coefficient + k] = this.m_array[lastr, lastc - k];
                        pos[3 * this.coefficient + k] = this.m_array[lastr - k, j];
                    }
                    this.CreatLine(i / (this.coefficient - 1), j / (this.coefficient - 1), pos);
                }
                else
                {
                    int cr = lastr - i + 1;
                    int cl = lastc - j + 1;
                    pos = new Vector3[(cr + cl) * 2];
                    for (int k = 0; k < cr; ++k)
                    {
                        pos[cl + k] = this.m_array[i + k, lastc];
                        pos[cr + 2 * cl + k] = this.m_array[lastr - k, j];
                    }
                    for (int k = 0; k < cl; ++k)
                    {
                        pos[k] = this.m_array[i, j + k];
                        pos[cr + cl + k] = this.m_array[lastr, lastc - k];
                    }
                    this.CreatLine(i / (this.coefficient - 1), j / (this.coefficient - 1), pos);
                }

                j = lastc;
            }
            i = lastr;
        }
    }

    /// <summary>
    /// 显示正六边形网格
    /// 正六边形边长最小为5，coefficient表示倍率
    /// </summary>
    private void ShowRegularHexagon()
    {
        this.coefficient = this.coefficient / 5;
        Vector3[] pos_1;
        Vector3[] pos_2;
        int num_1 = this.m_arrCol / (this.coefficient * (3 + 5)) * (this.coefficient * 5 + 1);
        int num_2 = this.m_arrCol % (this.coefficient * (3 + 5));
        if (num_2 > 0)
        {
            if (num_2 < 3 * this.coefficient)
            {
                num_2 = 1;
            }
            else
            {
                num_2 = num_2 - 3 * this.coefficient + 2;
            }
        }

        pos_1 = new Vector3[num_1 + num_2];
        pos_2 = new Vector3[num_1 + num_2];

        int rn = this.m_arrRow / (this.coefficient * (3 + 5));
        this.m_lines = new GameObject[rn, 2];
        for (int i = 4 * this.coefficient; i < this.m_arrRow;)
        {
            int index_1 = 0;
            int index_2 = 0;
            int r_1 = i - 4 * this.coefficient;
            int r_2 = i + 4 * this.coefficient;
            bool flag_1 = true;
            bool flag_2 = false;
            if (r_2 >= this.m_arrRow)
            {
                flag_1 = false;
            }

            for (int j = 0; j < this.m_arrCol;)
            {
                if (j % (this.coefficient * (3 + 5)) == 0)
                {
                    flag_2 = !flag_2;
                    if (flag_2)
                    {
                        pos_1[index_1++] = this.m_array[i, j];
                        if (flag_1)
                        {
                            pos_2[index_2++] = this.m_array[i, j];
                        }
                    }
                    else
                    {
                        pos_1[index_1++] = this.m_array[r_1, j];
                        if (flag_1)
                        {
                            pos_2[index_2++] = this.m_array[r_2, j];
                        }
                    }

                    j += 3 * this.coefficient;
                }
                else
                {
                    if (flag_2)
                    {
                        pos_1[index_1++] = this.m_array[r_1, j];
                        if (flag_1)
                        {
                            pos_2[index_2++] = this.m_array[r_2, j];
                        }
                    }
                    else
                    {
                        pos_1[index_1++] = this.m_array[i, j];
                        if (flag_1)
                        {
                            pos_2[index_2++] = this.m_array[i, j];
                        }
                    }

                    ++j;
                }
            }

            this.CreatLine(i / (2 * 4 * this.coefficient), 0, pos_1);
            if (flag_1)
            {
                this.CreatLine(i / (2 * 4 * this.coefficient), 1, pos_2);
            }

            i += (4 * this.coefficient * 2);
        }
    }

    /// <summary>
    /// 创建网格线
    /// </summary>
    private void CreatLine(int row, int col, Vector3[] pos)
    {
        if (this.m_lines[row, col] != null)
        {
            GameObject.Destroy(this.m_lines[row, col]);
        }
        this.m_lines[row, col] = new GameObject();

        LineRenderer _lineRenderer = this.m_lines[row, col].AddComponent<LineRenderer>();
        _lineRenderer.material = new Material(Shader.Find("Particles/Additive"));
        _lineRenderer.SetColors(this.gridColor, this.gridColor);
        _lineRenderer.SetWidth(this.gridLine, this.gridLine);
        _lineRenderer.useWorldSpace = true;
        _lineRenderer.SetVertexCount(pos.Length);
        for (int i = 0; i < pos.Length; ++i)
        {
            _lineRenderer.SetPosition(i, pos[i]);
        }

        this.m_lines[row, col].name = "CreateLine " + row + "  " + col;
        this.m_lines[row, col].transform.parent = transform;
        this.m_lines[row, col].transform.localPosition = new Vector3(7f + (col * 14),0, 7f + (row * 14));
    }
}